Abstract
In the light of experimental results, two case-control studies and one cohort study
in a population of ginseng cultivation area were conducted to confirm whether
ginseng has any anticarcinogenic effect on human cancers. All participants were
interviewed using a standardised questionnaire to obtain the information on demographics,
cigarette smoking, alcohol consumption and ginseng intake. In 905
pairs case-control study, 62% had a history of ginseng intake compared to 75%
of the controls, a statistically significant difference (p<0.01). The odds ratio (OR)
for cancer in relation to ginseng intake was 0.56. In extended case-control study
with 1987 pairs, the ORs for cancer were 0.37 in fresh ginseng extract users,
0.57 in white ginseng extract users, 0.30 in white ginseng extract users, 0.30 in
white ginseng powder users, and 0.20 in red ginseng users. Those who took
fresh ginseng slices, fresh ginseng juice, and white ginseng tea, however, did
not show decrease in the risk. Overall, the risk decreased as the frequency and
duration of ginseng intake increased. With respect to the site of cancer, the ORs
for cancers of the lip, oral cavity, pharynx, esophagus, stomach, colorectum,
liver, pancreas, larynx, lung and ovary were significantly reduced by ginseng
intake. Smokers with ginseng intake showed lower ORs for cancers of lung, lip,
oral cavity and pharynx and liver than those without ginseng intake. In 5 yr follow-
up cohort study conducted in the ginseng cultivation area, Kangwha-eup,
ginseng intakers had significantly lower risk than non-intakers. As for the type of
ginseng, cancer risk significantly decreased among intakers of fresh ginseng
extract, alone or together with other ginseng preparations. Among 24 red ginseng
intakers, no cancer death occurred during the follow-up period. The risk for
stomach and lung cancers was significantly reduced by ginseng intake, showing
a statistically significant dose-response relationship in each follow-up year. In
conclusion, Panax ginseng C.A. Meyer has been established as non-organ specific
cancer preventive, having dose response relationship. These results warrant
that ginseng extracts and its synthetic derivatives should be examined for
their preventive effect on various types of human cancers.